The drug propranolol has been used to treat performance anxiety for years, but a new study is the first to show that a single dose of the medication improves social skills of people with autism, making it easier to carry on a conversation. (Credit: iStockphoto)

Propranolol, a medication commonly used to treat high blood pressure and irregular heartbeats, shows potential to improve the social skills of people with autism.

“Propranolol was first reported to improve the language and sociability skills of individuals with autism in 1987, but it was not a randomized, controlled trial, and there has been little follow-up research on this drug in relation to autism,” says David Beversdorf, professor in the radiology, neurology, and psychological sciences departments at the University of Missouri.

“While its intended use is to treat high blood pressure, propranolol has been used off-label to treat performance anxiety for several years. However, this is the first study to show that a single dose of propranolol can improve the conversational reciprocity skills of individuals with autism.”

For the small study, 20 individuals with autism were given either a 40-milligram dose of propranolol or a placebo pill. An hour after administration, researchers had a structured conversation with the participants, scoring their performance on six social skills necessary to maintain a conversation: staying on topic, sharing information, reciprocity or shared conversation, transitions or interruptions, nonverbal communication, and maintaining eye contact. The total communication scores were significantly greater when the individual took propranolol compared to the placebo.

“Though more research is needed to study its effects after more than one dose, these preliminary results show a potential benefit of propranolol to improve the conversational and nonverbal skills of individuals with autism,” Beversdorf says.

“Next, we hope to study the drug in a large clinical trial to establish the effects of regular doses and determine who would most likely benefit from this medication. Additional studies could lead the way for improved treatments for individuals with autism.”

Graduate student Rachel Zamzow is lead author of the study published in the journal Psychopharmacology. Other researchers from the University of Missouri and from the University of Florida are coauthors of the study. The Health Resources and Services Administration supported the work.